Trussing arrangement for iron and cement constructions.



PATENTED' SEPT. 1, 1903.

DUMAS. TRUSSING- ARRANGEMENT FOR IRON AND CEMENT OONSTRUGTIONS.

APPLICATION FILED JUNE 30. 1902.

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No. 737,594. b PATENTED SEPT. 1, 1903..

' M. DUMAS.

TRUSSING ARRANGEMENT FOR IRON AND GEMENT-OONSTRUGTIONS.

APPLICATION FILED JUNE 30. 1902.

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. trusses together, is obviated.

Patented September 1, 1903.

PATENT OFFICE.

MAURICE DUMAS, OF BRUSSELS, BELGIUM.

TRUSSING ARRANGEMENT FOR IRON AND CEMENT CONSTRUCTIONS.

SPECIFICATION forming part of Letters Patent No. 737,594, dated September 1, 1903. Application filed June 301 1902. Serial No. 113,845. (No model.)

To all whom it may concern:

Be it known that I, MAURICE DUMAS, engineer, a citizen of the French Republic, residing at Brussels, Belgium, have invented a new and useful Trussing Arrangement for Iron and Cement Constructions; and I do hereby declare the following to be a full, clear, and exact description of the same.

This invention relates to a new trussing arrangement foriron and cement constructions, whatever purpose these constructions may be employed for.

The novelty of the invention lies in the arrangement of the lattice framework, and the invention is a real improvement upon trussings hitherto employed for the following reasons: First. The parts of the framework opposed to the sudden strains being inclined in the two directions present a normal metallic section to these strains, and this disposition is accordingly a proper one. Second. The winding of the parts of the framework over the bars insures a perfect binding together of the two trusses. Third. The combination of the guide-bar a, the lattice-work, and the rods constitutes a real metallic beam of suitable rigidity, which enables it to be moved from one locality to another and put in place without any fear of changes in the respective positions of these parts. Thus the bad work that may arise in consequence of the shifting of the trusses during the pugging, and which bungling is almost inevitable whatever care maybe exercised with constructions in which the concrete is the sole means of putting the This suitable resistance of the truss reduces the influence which the hold of the concrete has over the strength of the construction. It thus affords security in connection with the removal from the frame and enables such removal to be more rapidly effected. This trussin g arrangement thus possesses the advantages of iron trusses put together by bolts and rivets without their disadvantages.

The accompanying drawings for facilitatin g rangement. Fig. 2 is a transverse sectional view of Fig. 1 011 the line A B. Fig. 3 is a transverse sectional view showing a-slightlymodified arrangement of parts. Fig. 4 is a detail View, on an enlarged scale, showing portions of the elements which are comprised in myinvention. Fig. 5 is atransverse sectional view of Fig. 4. Fig. 6 is a detail view showing a slightly modified arrangement of parts. Fig. 7 is a transverse sectional viewof Fig. 6.

The trusses are divided into two groupsround bars and flat bars. They may be either of iron or of steel.

Round bcu*s.-These are of several kinds.

First. The bar indicated by a in the plan is the guide-bar. It runs through the whole length of the beam and the fiat bars, which form the trellis-work, are wound on it.

Second. The bars I) and 0 form, with the bar a, the tensional resistance necessitated by positive deflecting momenta.

Third. The bars d furnish under compression the necessary supplementary resistance when the concrete in compression is insufficient of itself to furnish the resistance necessitated by positive deflecting momenta.

Fourth. The bars f and g form'the tensional resistance necessitated by negative deflecting momenta.

Fifth. The bars h, which are rods of small diameter, connect the parts of the trelliswork and by the addition of the stays 1' enable the bars f and d to be combined with the trellis-work.

These five sorts of bars, which occur in the continuous beam, may be omitted in certain cases. Thus in the case of abeam placed on simple supports 7s, and consequently being without any grooved fitting, the bars f and g are dispensed with. In the same way when the concrete is sufficient for resisting alone in compression the bars d may likewise be omitted. The stays and the rods will also be omitted in this case, and the trellis-Work instead of being in the form shown in section in Fig. 2 will have that represented by Fig. 3. The round bars are thus intended to offer resistance under extension and compression. They form, in fact, the arms of the beam of which the trellis is the body.

The flat bars.-These are employed for making the trellis-work, the parts of which should resist the sudden strains and the horizontal sliding strains. This part of the trellis-work is formed by winding onto the guidebar a a flat bar j the two ends of which symmetrically incline over this guide-bar, take hold in the opposite arm of the beam and either on the corresponding bar, Fig. 2, or by being sealed in the concrete, Fig. 8. The mesh of the trellis-work varies in dimensions according to the sum of the sudden strain and the horizontal sliding strain, so that the section of the band j which forms it remaining the same the total section met by the strains at each point of the beam may be sufficient for resisting them. The combination of a guidebar and the corresponding parts constitutes a complete truss. The same piece of Work may be strengthened by one or more sets of these trusses arranged side by side.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that What I claim is 1. A trussing arrangement comprising essentially a metallic guide-bar, metallic bars 1), 0, extending longitudinally of and ad jacent to the guide-bar, and fiat metallic bars wound around the guide-bar at a point intermediate the length of said fiat bars, said fiat bars being arranged cooperatively to form a trellis-work, as described.

2. A trussing arrangement comprising essentially a metallic guide-bar, metallic bars I), 0, extending longitudinally of and adjacent to the guide-bar, the bars h arranged parallel to and longitudinal of the guide-bar and bars b, 0, but somewhat removed therefrom, and flat metallic bars wound around the guide-bar at a point intermediate the length of the said flat bars and having their opposite ends passing over the bars 72., the said flat bars being arranged to cooperatively form a trellis-work, as described.

3. A trussing arrangement comprising essentially a metallic guide-bar, metallic bars I), 0, extending longitudinally of and adjacent to the guide-bar, the bars h arranged parallel to and longitudinal of the guide-bar and bars I), 0, but somewhat removed therefrom, and flat metallic bars wound around the guide-bar at a point intermediate the length of the said flat bars and having their opposite ends passing over the bars 71, the said flatbars being arranged to cooperatively form a trellis-work, the bar d arranged longitudinally of and adjacent to the bars h and intermediate the sections of the flat bars, and the bar 2' extending transversely of the bars d, h, all in the manner and for the purpose specified.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

MAURICE DUMAS.

WVitnesses:

CHARLES HAROLD, GREGORY PHELAN. 

